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1.
Post-harvest losses for maize and beans are common storage challenges affecting Tanzania's smallholder and large-scale farmers' storage facilities. Consequently, this leads to a reduction of over 50% of harvested grain qualitatively and quantitively per year. Therefore, this experimental study was conducted at the entomological laboratory of the Sokoine University of Agriculture Tanzania, where the research was aimed to assess different common storage insect pests of beans and maize at Morogoro major markets (i.e., Kihonda, Mazimbu and Morogoro Central Market) with similar storage conditions in Morogoro municipality. The complete block design (CBD) with three experimental replications was used. Where locations (Kihonda, Mazimbu and Central market) markets were considered as experimental treatments. The results obtained show that there were no significant differences in number of insect pests (such as maize weevils and bean bruchids) identified between the Kihonda and Central markets (P > 0.05). However, there is a significant difference (P< 0.05) between Mazimbu and other markets regarding the number of insect pest multiplication resulting from the storage condition of those grains in a particular market. Nevertheless, continuous winnowing of stored grains was observed to significantly intensify the infestation of the storage pest in maize and common beans. Therefore, alternatively, to reduce insect pest infestation to maize and common beans in storage facilities, it is important to avoid constant winnowing of stored grains.  相似文献   
2.
The biology of the weevilBangasternus fausti (Reitter), the larvae of which live in the flowerheads ofCentaurea diffusa (De Lamarck) and some relatedCentaurea spp., was studied in the field and in the laboratory in northern Greece and in the laboratory in Rome, Italy. The species is univoltine and overwinters as adults. Under laboratory conditions adults lived up to 90 days and up to 359 eggs were deposited by a single female (n=18). The maximum number of eggs laid by a female per day was 12 and the maximum number of days a female laid eggs was 73. Generally, there is only one larva per seedhead. One-hundred percent seed destruction was recorded in 18.7% of 502 field collected seedheads, each with oneB. fausti egg. The average mortality of the species, from egg to adult, was 94.4% in the field during 1988 (n=200) and 95.8% during 1987 (n=502).   相似文献   
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The following new genus and seven new species of Cossonine weevils (Curculionidae: Cossoninae) are described from Dominican amber: Acamptus exilipes Poinar and Legalov, n. sp. (similar to A. rigidus), Caulophilus camptus Poinar and Legalov, n. sp. (similar to C. bennetti), Caulophilus elongatus Poinar and Legalov, n. sp. (similar to C. swensoni), Caulophilus ruidipunctus Poinar and Legalov, n. sp., Dryotribus pedanus Poinar and Legalov, n. sp. (similar to D. amplioculus), Ogygius obrieni Poinar and Legalov, n. gen., n. sp. (similar to the genus Apotrepus), and Stenotrupis pumilis Poinar and Legalov, n. sp. (similar to S. breviscapus). A key to the Dominican amber species of the genus Caulophilus is provided. Based on the extant weevil fauna, it appears that the Hispaniolan Cossonine were more diverse in the Tertiary than at present. http://zoobank.org/urn:lsid:zoobank.org:pub:14D1CFC0-4967-4D22-888B-0DE3E157D6BD  相似文献   
5.
A new species of Dryophthorus and two new species of Stenommatus (Coleoptera: Dryophthoridae) are described from Dominican amber. Dryophthorus microtremus n. sp. is characterised by monochrome dorsal scales, nearly parallel sides of the pronotum, wide elytral intervals and the elytral apex only slightly narrowed. Stenommatus tanyrhinus n. sp. is characterised by an elongate rostrum 4.5 times as long as wide in the middle. S. leptorhinus is characterised by small body size, a thin rostrum 3.0 times as long as wide in the middle, wide striae and a narrow prosternal process. This brings the total number of species of Dryophthorini in Dominican amber to five, which is more than half the number of extant species.http://www.zoobank.org/urn:lsid:zoobank.org:pub:4329D0DA-57BD-4CEA-9464-ABD5D1577FC9  相似文献   
6.
A small group of nine nominal species belonging to the genus Neacratus Alonso-Zarazaga, Lyal, Sforzi & Bartolozzi, 1999 is studied in detail from a morphological point of view. Lectotypes are designated for Brentus obtusus Lund, 1800 and Nemocephalus fulgidus Kleine, 1928. Three new synonymies are proposed: Nemocephalus brevicostatus Kleine, 1922 n. syn. for Brenthus obtusus Lund, 1800, Nemocephalus longiceps Perroud, 1853 n. syn. for Brenthus famulus Boheman, 1840, and Nemocephalus fulgidus Kleine, 1928 n. syn. for B. famulus Boheman, 1840. A new species, Neacratus pascali n. sp., is described from French Guiana. New country records are provided for Neacratus obtusus (Bolivia, Ecuador, French Guiana, Grenada, Peru, Trinidad and Tobago, Venezuela), N. puncticeps (Sharp, 1895) (Colombia, Ecuador, Venezuela), N. guatemalensis (Senna, 1893) (Belize, Colombia, El Salvador), N. deplanatus (Sharp, 1895) (Colombia, Costa Rica, French Guiana, Mexico, Panama, Venezuela) and N. famulus (Paraguay). A phylogenetic analysis carried out on this group shows it forms a monophyletic lineage included in a clade containing most of other species of Neacratus, of which it is the type species; it is therefore not justified to create a new generic name. The possible polyphyletism of the genus Neacratus as a whole and the development of an excessively long rostrum in some male Acratini are discussed.  相似文献   
7.
New species of rhynchitid weevils, Rhynchitobius tanyrhinus n. sp. and R. xuthocolus n. sp. (Coleoptera: Rhynchitidae) in the tribe Auletini are described from Dominican amber. The former species is characterized by a long rostrum, narrow pronotum and elytra, rugose elytral intervals and distinct elytral striae. The latter species has a short rostrum, wide antennal club, yellow legs, non-rugose elytral intervals and weak elytral striae. The present study describes the first representatives of the family Rhynchitidae from Dominican amber.  相似文献   
8.
Loss in seed yield and therefore decrease in plant fitness due to simultaneous attacks by multiple herbivores is not necessarily additive, as demonstrated in evolutionary studies on wild plants. However, it is not clear how this transfers to crop plants that grow in very different conditions compared to wild plants. Nevertheless, loss in crop seed yield caused by any single pest is most often studied in isolation although crop plants are attacked by many pests that can cause substantial yield losses. This is especially important for crops able to compensate and even overcompensate for the damage. We investigated the interactive impacts on crop yield of four insect pests attacking different plant parts at different times during the cropping season. In 15 oilseed rape fields in Sweden, we estimated the damage caused by seed and stem weevils, pollen beetles, and pod midges. Pest pressure varied drastically among fields with very low correlation among pests, allowing us to explore interactive impacts on yield from attacks by multiple species. The plant damage caused by each pest species individually had, as expected, either no, or a negative impact on seed yield and the strongest negative effect was caused by pollen beetles. However, seed yield increased when plant damage caused by both seed and stem weevils was high, presumably due to the joint plant compensatory reaction to insect attack leading to overcompensation. Hence, attacks by several pests can change the impact on yield of individual pest species. Economic thresholds based on single species, on which pest management decisions currently rely, may therefore result in economically suboptimal choices being made and unnecessary excessive use of insecticides.  相似文献   
9.
As a result of field tests in Bulgaria and Hungary, cis‐2‐isopropenyl‐l‐methylcyclobutane ethanol (racemic grandisol) is reported for the first time as an attractant for Bothynoderes affinis (Schrank) (Coleoptera: Curculionidae, Lixinae), a member of the pest weevil complex of sugar beet. Dose–response experiments in the field using Csalomon TAL (modified pitfall) traps (Plant Protection Institute, CAR HAS, Budapest, Hungary) showed that catches of B. affinis adults increased with increasing attractant dose. In a subsequent experiment studying the effect of trap color (white, blue, yellow, fluorescent yellow, and transparent) all traps with the lure caught more than non‐baited control traps, and the highest number of adults was recorded in transparent and yellow baited traps. Trap color had a significant effect on the number of B. affinis females captured. Transparent TAL traps baited with 1–10 mg grandisol applied on rubber dispensers are recommended for the detection and monitoring of B. affinis. In addition to the target species, 17 other Lixinae species were captured during the field experiments, demonstrating for the first time the possible role of grandisol in the chemical communication systems of some of these species. A second locality of Lixus punctiventris Boheman (Lixinae, Lixini) in Bulgaria is reported. TAL traps baited with grandisol might be a useful tool for surveying Lixinae diversity in different biotopes.  相似文献   
10.
The weevil genus Azotoctla gen. nov. (Coleoptera: Curculionidae: Curculioninae: Acalyptini Thomson), is described to accommodate the following 15 new Neotropical species: Azotoctla aecuatorialis sp. nov. (Ecuador), Azotoctla anerunca sp. nov. (Ecuador), Azotoctla angustacra sp. nov. (Ecuador), Azotoctla curvirostra sp. nov. (Peru), Azotoctla dasygastra sp. nov. (Costa Rica and Honduras), Azotoctla femorata sp. nov. (Colombia, Costa Rica, Ecuador and Panama), Azotoctla gomezi sp. nov. (Colombia, Costa Rica and Panama), Azotoctla gottsbergeri sp. nov. (Brazil), Azotoctla clemmyssa sp. nov. (Colombia), Azotoctla melolauta sp. nov. (Colombia), Azotoctla migueli sp. nov. (Colombia), Azotoctla nana sp. nov. (Panama), Azotoctla punctata sp. nov. (Costa Rica), Azotoctla tibiatra sp. nov. (Belize), and Azotoctla tuberquiai sp. nov. (Colombia). Azotoctla is placed in the tribe Acalyptini, subtribe Staminodeina Franz, thus representing the sister taxon of Staminodeus Franz. The monophyly of Azotoctla is supported by the following inferred traits: a noncarinate rostrum that is tumescent above the antennal insertion in males; equilaterally subtriangular hemisternites of the male sternum 8; paired, longitudinal, laterally positioned sclerites of the aedeagus; and a bifurcate lamina of the female sternum 8, which bears explanate, diverging furcal arms. A key to the species of Azotoctla is provided; and the salient features of each species are illustrated and presented along with distributional and natural history data. A morphological cladistic analysis of 23 terminal species (eight outgroup, 15 ingroup) and 33 characters yielded a single most parsimonious cladogram (length = 75 steps, consistency index = 52, retention index = 77), with the ingroup topology ((A. aecuatorialis, (A. anerunca, A. gottsbergeri)), (A. punctata, ((A. angustacra, A. nana), (A. tibiatra, (A. clemmyssa, (A. curvirostra, A. femorata)), (A. melolauta, ((A. gomezi, A. migueli), (A. dasygastra, A. tuberquiai))))))). Species of Azotoctla are reproductively associated with the ephemeral staminodes of different members of the Neotropical monocot family Cyclanthaceae; most commonly with the widespread genus Carludovica Ruiz & Pavón. The interspecific homogeneity in external morphology, coupled with marked differences in genital traits and an apparent absence of narrow geographical ranges mediated by either host plants and/or biogeographical factors, jointly suggest that the diversification of Azotoctla is a relatively recent phenomenon and driven strongly by sexual selection. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 166 , 559–623.  相似文献   
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